set term png
set output "poisson2d_2pointcharge.png"
unset border
#set xrange [0:100]
#set yrange [0:100]
#set xtics ("0.0" 0, "0.2" 20, "0.4" 40, "0.6" 60, "0.8" 80, "1.0" 99)
#set ytics ("0.0" 0, "0.2" 20, "0.4" 40, "0.6" 60, "0.8" 80, "1.0" 99)
unset xtics
unset ytics
plot "poisson2d_2pointcharge.txt" matrix with image
